Variation is NOT being used to explain variation. If this were true, you would actually be able to show me EVEN ONE research paper that does this. Please put forth some evidence that shows variation being used to explain variation or remove variation from box 1. I am relatively sure that you will do neither since that would damage your baseless assertions.

You'll now claim that using the observation of some organisms being weeded out by their relative unfitness to the environment in comparison to other organisms within their species (Natural Selection) as evidence of the change in population characteristics over time (Evolution) is circular. Of course, since you don't know what circular reasoning is (despite bringing it up yourself), doing that is just as valid as anything else you've done in this thread so far.

The existence of stars is actually evidence in favor of astrology being true. If there were no stars, astrology could not claim that stars were an influence over our lives. This doesn't make astrology true it just provides some very minimal support.
Jerusalem exists and has been shown to exist for quite some time. It's existence provides evidence that the claims of the Bible are true since the Bible does mention Jerusalem. Jerusalem also provides evidence that the claims of the Koran are true since the Koran mentions Jerusalem. The evidence (existence of Jerusalem for a long period of time) DOES NOT make either or both of those writings true, it is only evidence in favor of the claim that those writings are true.

Variation as evidence of the validity of the Theory of Evolution, DOES NOT make evolution true. It is only evidence in favor of the evolution, and using it as evidence is not circular according to the definition of circular reasoning that YOU pointed out.